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  • How do traction motor blowers work?

  • General discussion about locomotives, rolling stock, and equipment
General discussion about locomotives, rolling stock, and equipment

Moderator: John_Perkowski

 #902667  by slashmaster
 
If I'm not mistaken, a traction motor blower is a huge squirrel cage fan that partially sticks out of the left side of a locomotive right? Does it blow through tubes to each traction motor on both trucks? Does it wait until the traction motors heat up or is it always running? What voltage do they run at?
 #902747  by Jtgshu
 
On older EMD diesels (and newer ones too im assuming) the TM blowers constantly blow. Im familiar with the GP40s models

However, on some electric locos, ALP44s and ALP46s which I run, especially the ALP44s, they shut off if sitting for a long time and turn on when they start to move, if temperature allows of course

This vid shows the traction motor blowers kicking up a notch, they weren't off, but on a lower speed, but when the train started to move they turn on more powerful. I can't find one of them all the way off and turning on from a stop tho

http://www.youtube.com/watch?v=Vc7ktKi5 ... re=related
 #902898  by slashmaster
 
Jtgshu wrote:On older EMD diesels (and newer ones too im assuming) the TM blowers constantly blow. Im familiar with the GP40s models

However, on some electric locos, ALP44s and ALP46s which I run, especially the ALP44s, they shut off if sitting for a long time and turn on when they start to move, if temperature allows of course

This vid shows the traction motor blowers kicking up a notch, they weren't off, but on a lower speed, but when the train started to move they turn on more powerful. I can't find one of them all the way off and turning on from a stop tho

http://www.youtube.com/watch?v=Vc7ktKi5 ... re=related
Thanks for the reply, so I guess they're not 3 phase like the radiator fans are. I've been hearing that sound in other loco's and wondered if that's what it was. Can you actually see these blowers in what you run? Or are they covered?
 #902937  by DutchRailnut
 
The traction motor blowers are powered of 3 phase auxihiliary coils on Main Generator.
at Idlle the blowers just barely spin but once engine notches up the speed increases quickly.
the same circuit powers the radiator fans on EMD's
 #903109  by timz
 
"a huge squirrel cage fan that partially sticks out of the left side of a locomotive right?"

Fans have been known to refer to a "blower bulge" on the side of the hood, but I don't think they're talking about the TM blower. It's inside.

On older EMDs (which includes the F40?) the TM blower is connected directly to the engine-- it isn't electrically driven at all.
 #903311  by Allen Hazen
 
The description "a huge squirrel cage fan that partially sticks out of the left side of a locomotive" sounds more like traction motor blowers on some early electric locomotives than like those on modern diesels. Diesel tr. mo. bls. tend to use air that is already inside the carbody, and do't show externally.

If you go to George Elwood's "Fallen Flags" rail photo sites
http://rr-fallenflags.org/
and go to the "Operator's Manuals" section you will find a number of operator's manuals for assorted diesel (and some electric) locomotives: most of these will contain diagrams showing the location of various pieces of equipment on the locomotive, which will show where the t.m.b.s are. (Older locomotives-- first generation diesels, from the 1930s 1940s 1950s -- had separate blowers, either one per motor or one at each end of the locomotive, either driven directly from the engine or run by separate electric motors. I think more modern ones usually have a single blower, with ducts carrying the air to the traction motors and other equipment that needs cooling air.)

Since the 1980s, locomotives have had on-board computers monitoring and controlling many aspects of their performance. My guess is that (in order to reduce power needs, and so fuel consumption) blowers are now computer-controlled, and only run when (and at the speed) needed.
 #904633  by railroadcarmover
 
I own an H2-44 Fairbanks locomotive and the cab end / rear truck traction motor blower assembly is directly ( shaft) connected to the other end of the "radiator fan motor generator". This RFMG is used to generate 165 vdc to power the radiator compartment fan motor. The RFMG is belt coupled to the air compressor assembly.

The front truck / traction motor blower assembly on the other hand is powered by a 75 volt dc 62 amp 5 HP motor.
I need to swap mine out since the motor has bad bearings. I have a spare one to install luckily.
 #904689  by slashmaster
 
railroadcarmover wrote:I own an H2-44 Fairbanks locomotive and the cab end / rear truck traction motor blower assembly is directly ( shaft) connected to the other end of the "radiator fan motor generator". This RFMG is used to generate 165 vdc to power the radiator compartment fan motor. The RFMG is belt coupled to the air compressor assembly.

The front truck / traction motor blower assembly on the other hand is powered by a 75 volt dc 62 amp 5 HP motor.
I need to swap mine out since the motor has bad bearings. I have a spare one to install luckily.
Very interesting! So it only has one radiator fan? How big is it? Interesting the other blower is 75 volts. I thought all locomotives had 60 volt systems from the batteries?
 #905024  by DutchRailnut
 
Locomotives have 64 volt batteries,or 8 times 8 volt battery with a charging voltage of 74 volt.
 #905935  by railroadcarmover
 
slashmaster wrote:
railroadcarmover wrote:I own an H2-44 Fairbanks locomotive and the cab end / rear truck traction motor blower assembly is directly ( shaft) connected to the other end of the "radiator fan motor generator". This RFMG is used to generate 165 vdc to power the radiator compartment fan motor. The RFMG is belt coupled to the air compressor assembly.

The front truck / traction motor blower assembly on the other hand is powered by a 75 volt dc 62 amp 5 HP motor.
I need to swap mine out since the motor has bad bearings. I have a spare one to install luckily.
Very interesting! So it only has one radiator fan? How big is it? Interesting the other blower is 75 volts. I thought all locomotives had 60 volt systems from the batteries?
There is only one fan motor and it is rated at 27HP with a max voltage of 165volts and 120 amps.
It weighs 560 lbs. Its a series wound configuration.
 #907642  by slashmaster
 
railroadcarmover wrote:
slashmaster wrote:
railroadcarmover wrote:I own an H2-44 Fairbanks locomotive and the cab end / rear truck traction motor blower assembly is directly ( shaft) connected to the other end of the "radiator fan motor generator". This RFMG is used to generate 165 vdc to power the radiator compartment fan motor. The RFMG is belt coupled to the air compressor assembly.

The front truck / traction motor blower assembly on the other hand is powered by a 75 volt dc 62 amp 5 HP motor.
I need to swap mine out since the motor has bad bearings. I have a spare one to install luckily.
Very interesting! So it only has one radiator fan? How big is it? Interesting the other blower is 75 volts. I thought all locomotives had 60 volt systems from the batteries?
There is only one fan motor and it is rated at 27HP with a max voltage of 165volts and 120 amps.
It weighs 560 lbs. Its a series wound configuration.
Interesting, are you saying just the motor weighs 560 or the whole assembly with the blower and fan weighs 560?
 #908018  by BigLou80
 
DutchRailnut wrote:Locomotives have 64 volt batteries,or 8 times 8 volt battery with a charging voltage of 74 volt.
Are the lead acid batteries? I thought all lead acid cells were in 1.5 volt increments.
 #908020  by BigLou80
 
Is there are reason traction motors are air cooled and not sealed liquid cooled units ? seems like sealed traction motors would be a lot more durable and solve some of the problems with snow/water shorting them out.